1. Field of the Invention
The present invention relates to electronic devices such as an electronic calculator with a touch screen and a computer-readable medium storing a control program of the electronic device.
2. Description of the Related Art
In conventional calculators, in order that a mathematical formula is displayed while transforms such as “reciprocal”, “decimal→fraction”, “fraction→decimal”, “factorization”, and “expansion” are performed for the mathematical formula, it is necessary for a user to select an item from a menu or input a command, and to learn a complicated key manipulation.
In a conventional calculator having a graphic drawing function, in order that a graphic is displayed while an angle or a line segment of the graphic is changed and deformed, similarly to the case in which the mathematical formula is displayed while transformed, it is necessary to learn a more complicated key manipulation such that the item is selected from the menu or the command is input.
On the other hand, for example, Jpn. Pat. Appln. KOKAI Publication No. 2009-015388 discloses a graph scientific calculator, in which a touch panel is mounted, and a touch manipulation can be performed on the touch panel to select the item of the menu or to provide the command instead of the key and mouse manipulations, thereby improving operability.
The touch panel is merely used instead of the mouse or the key in the conventional graph scientific calculator on which the touch panel is mounted, and the touch panel is used only as a continuation of a conventional input method in which “the displayed item is selected and input”.
On the other hand, in an electronic device on which a touch panel is mounted to display an image, there is a function of touching and moving the display image or spreading or narrowing a touch width by multi touch, thereby intuitively enlarging or contracting the display image.
However, in the conventional electronic devices, the mathematical formula cannot be displayed while transformed in response to the user's intuitive touch manipulation performed for the mathematical formula on the display screen.